Hey Guys,

Got another problem, one that even after reading the stuff on here, I can’t pinpoint. A little back story first. The other day I pulled into my grandma’s front yard so I would be off the road; well my back tires sunk into a snow pile and I started to spin. I thought ok no big deal, so I hit the brakes to make sure the tires were stopped, straightened the front wheels and then hit the 4Hi button. I heard the TCCM click, and then heard the transfer case engage, all good I thought, well I was wrong. I hit the gas and once again the back tires just spun. At that point my dad came out and watched and he said that only my back tires were spinning, the fronts weren’t doing anything. So after a lot of cussing and digging out, I was able to pull out in 2WD. After I left my grandma’s I tried to make the drive train bind up so I knew it was engaging, but the truck refused to bind up.

Fast forward to today (First nice day we’ve had) and I went out to take a look. Here is what I did:
1.Pulled the Switch from the dash and checked to make sure that was fine and it was fine
2.Pressed the 4 Hi button and the transfer case engaged, and locked the driveshaft
3.I pulled battery tray and checked the actuator, and it did exactly what it is supposed to do, retracting about ½- ¾ of an inch.
4.I then jacked the front wheels up one at a time, and tried to spin the front tires while it was locked in 4Hi and the tranny in Drive, and the tires would not spin.
5.I then popped the kick panel off and checked the TCCM for corrosion and there was none
6.I then had my girlfriend pull the truck forward in 4Hi while I lay beside the truck and watched the underside. While she pulled forward I could see the front driveshaft turning as if it was powering the front wheels
7.By this time I am completely pi**ed off and decided to take it up to a gravel lot with a small mud hill beside it. When I tried to do this (In 4wd), the backs once again spun and the front did absolutely nothing.
8.I checked to make sure the connector on the front differential was good and I noticed no corrosion or anything of that nature so I assume that’s good.

At that time I just gave up, and decided to see if any of you guys had an idea. On a side note, I replaced the switch on the transfer case about a year and a half ago, and have not had any problems with the system until now. I have the NV 233 Transfer Case.

Thanks again guys

 

Things don't add up. If everything is locking in, there should be power getting to the front end. The checks that you have done confirm that the transfer case is locking in and that the front axle is locking in. With the NV233 transfer case, there is gear to gear contact when in 4HI (i.e. no viscous coupling like in the NV236 transfer case). So it is either locked in or not.

One check that you should also try is to disconnect and plug the vacuum line to the front axle. Then engage 4wd and see if the front driveshaft spins. Try to turn it with a pipe wrench if you have to so that you can say for certain that it is locked in. Before you engage it in 4wd, it should turn relatively freely. After that without the front axle engaged, it should not turn at all.

 

Thanks for getting back to me, I appreciate it. I was so pi**ed off I kept digging around on here, and just on the internet in general, and I found a guy somewhere elsee that was having a similar problem. Come to find out it was a vacuum plug that was supposed to have a plug in it, and the plug had come out at some point, somewhere, lord knows how. I blocked the hose off like the other guy said and BAM i have 4WD again, I went and tested it out and the front tires were spinning so I guess maybe it had enough to sort of lock it in, but not all the way? I don't know though. It goes in for a check up in two weeks, I'll have a mechanic look at it and see what we says.

Thanks again though,
Jeff

 

OK, I've got another question based on the same problem. I've been reading on here that there is a vacuum reservoir on the fender. I have a random rose coming off a tee by the brake booster and after reading things on here, I have come to the conclusion that this random hose is supposed to go into this vacuum reservoir.

Here is my problem: Where is this vacuum reservoir, and where does the hose go into it?

If anyone has a picture of this, it would help me a lot. As of right now, I just have the hose blocked off, but I'd like to get the hose back to where it belongs.

Thanks

 

Very common problem and question. The vacuum reservoir is located INSIDE the driver side fender. If the hose has just come off the nipple, it is a simple fix. Just plug it back in. If the nipple has broken off, carefully remove it from the vacuum line and get some 2-part epoxy specifically for plastics (not the multi use stuff) and stick it back on.